Patent Application
20210218311
The present disclosure relates to electric machines, and more particularly to phase to phase terminal lead protection for electric machines.
Electric machines such as generators can have brazed terminal leads. In the event of FOD (foreign object debris) being introduced to the electric machine, it is sometimes possible for the FOD to short circuit the electric machine, e.g., if the FOD is metallic and contacts two of the terminal leads.
The conventional techniques have been considered satisfactory for their intended purpose. However, there is an ever present need for improved systems and methods for electric machines. This disclosure provides a solution for this need.
A system includes a pair of terminal leads joined together. An insulative sleeve is wrapped around the pair of terminal leads. Lacing binds around the insulative sleeve.
Cured epoxy can encase the insulative sleeve and lacing. The insulative sleeve can include fiberglass. The insulative sleeve can be wrapped more than 360° around the pair of terminal leads so that a first edge of the insulative sleeve is tucked under a second edge of the insulative sleeve.
The pair of terminal leads can be brazed together. The terminal leads can be mounted to a terminal block. The pair of terminal leads can be a single pair of terminal leads. One or more additional pairs of terminal leads can be mounted to the terminal block, wherein each additional pair of terminal leads has a respective insulative sleeve wrapped around it. The terminal block can be mounted to an electric machine housing. The pair of terminal leads can be electrically connected to a stator of the electric machine.
A method includes brazing together a pair of terminal leads and wrapping the pair of terminal leads in an insulative sleeve after brazing. The method includes binding the insulative sleeve to the pair of terminal leads.
The method can include spreading epoxy over the sleeve and curing the epoxy. The method can include cutting a fiberglass sleeve into a sheet with opposed first and second edges for use as the insulative sleeve before wrapping the pair of terminal leads in the insulative sleeve. Wrapping the pair of terminal leads in the insulative sleeve can include wrapping the insulative sleeve more than 360° around the terminal leads so that the first edge of the insulative sleeve is tucked under the second edge of the insulative sleeve. The pair of terminal leads can be mounted to a terminal block and the method can include mounting the terminal block to an electric machine housing. The method can include electrically connecting the terminal leads to a stator in the electric machine housing. The method can include comprising wrapping at least one additional pair of terminal leads in a respective insulative sleeve.
These and other features of the systems and methods of the subject disclosure will become more readily apparent to those skilled in the art from the following detailed description of the preferred embodiments taken in conjunction with the drawings.
So that those skilled in the art to which the subject disclosure appertains will readily understand how to make and use the devices and methods of the subject disclosure without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to certain figures, wherein:
Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. For purposes of explanation and illustration, and not limitation, a partial view of an embodiment of a system in accordance with the disclosure is shown in
System 100 includes a terminal block 102 mounted to an electric machine housing 104 of an electric machine 106, e.g., a generator for aerospace applications. Four pairs of terminal leads 108 are mounted to the terminal block 102. Those skilled in the art will readily appreciate that any suitable number of pairs of terminal leads 108 can be used without departing from the scope of this disclosure. A respective wire 110 electrically connects each pair of terminal leads 108 a stator 112 of the electric machine 106. Each pair of terminal leads 108 are joined together, e.g. the respective leads 114 and 116 in each pair of terminal leads 108 can be brazed together, as indicated in
With reference now to
With reference now to
The procedure to this point can be performed on all four (or any other suitable number) of the pairs of terminal leads 108 shown in
The methods and systems of the present disclosure, as described above and shown in the drawings, provide for phase to phase terminal lead isolation and protection with superior performance relative to traditional techniques. While the apparatus and methods of the subject disclosure have been shown and described with reference to preferred embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the subject disclosure.
